CN111690821B - Continuous converting process for high-grade matte - Google Patents

Continuous converting process for high-grade matte Download PDF

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CN111690821B
CN111690821B CN202010583593.4A CN202010583593A CN111690821B CN 111690821 B CN111690821 B CN 111690821B CN 202010583593 A CN202010583593 A CN 202010583593A CN 111690821 B CN111690821 B CN 111690821B
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furnace
converting
matte
temperature
copper
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CN111690821A (en
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蹇冬冬
孙殿强
贺瑞萍
王新民
袁俊智
安强
吴稳柱
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Huading Copper Development Co ltd
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    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22BPRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B15/00Obtaining copper
    • C22B15/0026Pyrometallurgy
    • C22B15/0028Smelting or converting
    • C22B15/003Bath smelting or converting
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22BPRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B5/00General methods of reducing to metals
    • C22B5/02Dry methods smelting of sulfides or formation of mattes
    • C22B5/12Dry methods smelting of sulfides or formation of mattes by gases
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00Technologies related to metal processing
    • Y02P10/20Recycling

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Abstract

The invention discloses a high-grade matte continuous converting process, which comprises the following steps: step S1: the hot copper matte is quantitatively and periodically sent into the converting furnace according to 24 tons/hour through a connecting chute; step S2: opening a compressed air valve and an oxygen valve, supplying air and oxygen into the furnace, and then turning the furnace body to a blowing position for blowing; step S3: in the converting process, converting slag, copper matte and blister copper to form a three-phase structure, and maintaining the temperature of a copper matte layer in a reaction area at 1200 +/-50 ℃; determining the liquid level in the furnace by measuring the thicknesses of the converting slag layer, the matte layer and the coarse copper layer, so that converting slag is discharged from a slag discharge port in time, and the liquid level of the coarse copper layer is discharged from a copper outlet when reaching an oxygen lance port; in the invention, matte with the grade of 76-78% is selected as a converting raw material, pure air is adopted for converting, the hot matte is 24 tons per hour, the full hot material converting of the bottom blowing continuous converting furnace is ensured, no intermediate cold material is added to control the melt in the furnace, and the continuous converting production of the hot matte is realized.

Description

Continuous converting process for high-grade matte
Technical Field
The invention belongs to the technical field of crude copper smelting, and particularly relates to a high-grade matte continuous converting process.
Background
In the traditional production process, in the blowing process of hot copper matte, because the grade of the hot copper matte is low (the grade of the copper matte is controlled to be 68-70%), the generated heat energy cannot be balanced, and an intermediate material needs to be added into the furnace for cooling treatment, so that the heat balance is achieved. This requires the external exothermic copper matte at the early stage of the furnace to slowly cool, accumulating a large amount of intermediate material. When production, carry the stove through the belt in, come the controlled temperature, need carry out vehicle transportation, breaker breakage at slow cooling in-process, need increase the indispensable production facility such as transportation belt, feed bin specially moreover, indirectly cause manufacturing cost's increase, a large amount of intermediate stocks also can cause the fund to overstock, influence the operation of company.
Secondly, in the blowing process, the oxygen lance is positioned in a blister copper layer, the heat balance in the furnace is not easy to control due to the complex material entering the furnace, the liquid level of the fusant in the furnace is high or low, the oxygen lance and the oxygen lance brick are easy to burn, and the service life of the furnace body is influenced.
Disclosure of Invention
The invention provides a high-grade matte continuous converting process aiming at the technical problems, and the full-heat material production is realized according to the principle of low grade high heat energy, so that intermediate materials do not need to be accumulated, the work of crushing and the like is also not needed, the link of belt conveying is omitted, the production process is simplified, and the production cost is saved.
The technical scheme adopted by the invention is as follows:
a high-grade matte continuous converting process comprises the following steps:
step S1: the smelting bottom-blown converter regularly feeds the thermal state matte into the converting furnace according to the ration of 24 tons/hour through a connecting chute;
step S2: opening a compressed air valve and an oxygen valve, supplying air and oxygen into the furnace through an oxygen lance, keeping the total air quantity entering the furnace at 9000 plus 12000Nm/h, keeping the oxygen quantity entering the furnace at 500 plus 1200Nm/h, and keeping the oxygen-enriched oxygen concentration in the furnace at 21.3-25%, and then transferring the furnace body to a converting position for converting;
step S3: in the converting process, converting slag, copper matte and crude copper into a three-phase structure according to different specific gravities, wherein the temperature of a copper matte layer in a reaction zone is maintained at 1200 +/-200 ℃; determining the liquid level in the furnace by measuring the thicknesses of the converting slag layer, the matte layer and the coarse copper layer, so that converting slag is discharged from a slag discharge port in time, and the liquid level of the coarse copper layer is discharged from a copper outlet when reaching an oxygen lance port;
step S4: and judging the temperature of the furnace body, when the furnace temperature is higher, improving the grade of matte, improving the air inlet amount of the converting furnace, reducing the oxygen inlet amount, and adding a residual electrode into the furnace to adjust the furnace temperature so as to keep the furnace temperature at 1200 +/-50 ℃.
Preferably, in step S1, the thermal matte grade is 76% to 78%.
Preferably, in the step S2, the total air quantity into the furnace is kept at 12000Nm/h, the oxygen quantity into the furnace is kept at 500-1200Nm/h, and the oxygen-enriched oxygen concentration in the furnace is 21.3%.
Preferably, in the step S2, the lance entry angle is set to be 30-60 degrees; the injection point of the oxygen lance is positioned on the ice copper layer.
Preferably, the angle of the oxygen lance furnace is set to be 49 degrees, the vertical height of the lower edge of the oxygen lance port from the furnace bottom is 500mm, and the injection point of the oxygen lance is positioned at the junction of the rough copper layer and the matte layer.
Preferably, the oxygen lance adopts double channels, the inner channel is filled with mixed gas of oxygen and compressed air, the outer channel is filled with compressed air, and the pressure of the outer channel is kept higher than that of the inner channel.
Preferably, in step S3, the air inlet amount and the oxygen amount are adjusted to maintain the furnace inlet pressure stable by using two modes of the large air amount low oxygen concentration and the small air amount high oxygen concentration according to the furnace temperature and the blowing speed during the blowing process.
Compared with the prior art, the invention has the beneficial effects that:
1. in the invention, matte with the grade of 76-78% is selected as a converting raw material, pure air is adopted for converting, the hot matte is 24 tons per hour, the full hot material converting of the bottom blowing continuous converting furnace is ensured, no intermediate cold material is added to control the melt in the furnace, the temperature (1210 ℃) required by normal production can be reached, and the continuous converting production of the hot matte is realized.
2. The furnace entrance angle of the oxygen lance is set to be 30-60 degrees, the oxygen lance is always positioned at the joint of the matte layer or the matte layer and the blister copper layer, the injection point of the oxygen lance is kept at the matte layer, and the matte layer is a reaction area, so that the high temperature (1200 ℃) is maintained, and the temperature change fluctuation is small, so that the loss of the oxygen lance is smaller.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
FIG. 1 is a schematic structural diagram of the relationship between the positions of an oxygen lance and a furnace body in a continuous high-grade matte converting process according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention aims to reasonably improve the grade of the copper matte, and realizes full-heat material production according to the principle of high grade and less heat energy, so that intermediate materials do not need to be accumulated, and crushing and other work do not need to be carried out. According to the principle, the following experiments are carried out on the traditional process, which is shown in the table I: (21.3% oxygen in air).
Figure BDA0002553846810000041
On the basis of the production mode of the traditional process, the production parameters are gradually adjusted, experiments are carried out, and the result is finally obtained under the condition that the furnace inlet air quantity is constant (12000 (Nm)3H), matte grade of smelting furnace76-78% and pure air blowing is adopted, the hot matte is 24 tons per hour, the full hot material blowing of the bottom blowing continuous converting furnace can be ensured, and any intermediate cold material is not added to control the melt in the furnace, so that the temperature (1210 ℃) required by normal production is reached.
Example 1
The continuous converting process for the high-grade matte in the embodiment comprises the following steps:
step S1: the smelting bottom blowing furnace quantitatively and periodically sends the thermal state copper matte into the blowing furnace according to 24 tons/hour through a connecting chute, wherein the grade of the thermal state copper matte is 76-78%;
step S2: opening a compressed air valve and an oxygen valve, setting the furnace entering angle of the oxygen lance to be 30 degrees, setting the distance between the mouth of the oxygen lance and the furnace bottom to be 190mm, always positioning the oxygen lance at the joint of the matte layer and the blister copper layer, directly supplying air and oxygen to the matte layer in the furnace through the oxygen lance, keeping the total air quantity entering the furnace to be 12000Nm/h, keeping the furnace entering oxygen quantity to be 500-1200Nm/h and the oxygen-enriched oxygen concentration in the furnace to be 21.3 percent, and then transferring the furnace body to a converting position for converting;
step S3: in the converting process, converting slag, matte and crude copper into a three-phase structure according to different specific gravities, wherein the temperature of a matte layer in a reaction zone is maintained at 1210 ℃; determining the liquid level in the furnace by measuring the thicknesses of the converting slag layer, the matte layer and the coarse copper layer, so that converting slag is discharged from a slag discharge port in time, and the liquid level of the coarse copper layer is discharged from a copper outlet when reaching an oxygen lance port;
step S4: when the converting furnace is used for slag and copper discharging, the temperature measuring gun is used for measuring the temperature of the converting furnace, the shaking frequency of the molten solution in the converting furnace is observed from the observation window, if the shaking frequency is high, the temperature is high, otherwise, the temperature is low, the temperature of the molten solution in the converting furnace is comprehensively judged through the shaking frequency and the measured temperature data of the temperature measuring gun, if the furnace temperature is high, the grade of matte is improved, the air inlet amount of the converting furnace is increased, the oxygen inlet amount is reduced, and the furnace temperature is adjusted by adding a residual electrode into the converting furnace, so that the furnace temperature is kept at 1200 +/-50 ℃.
In the blowing process, according to the temperature in the furnace and the blowing speed, the air inlet quantity and the oxygen quantity are adjusted by adopting two modes of large air quantity low oxygen concentration and small air quantity high oxygen concentration, so that the pressure in the furnace is kept stable.
Example 2
The continuous converting process for the high-grade matte in the embodiment comprises the following steps:
step S1: the smelting bottom blowing furnace is used for quantitatively and periodically feeding the thermal state matte into the blowing furnace according to the proportion of 24 tons/hour, wherein the thermal state matte grade is 76-78%;
step S2: opening a compressed air valve and an oxygen valve, setting the furnace entering angle of an oxygen lance to be 49 degrees, setting the vertical height of the lower edge of an oxygen lance port to be 500mm from the bottom of the furnace, and setting the injection point of the oxygen lance at an ice copper layer, directly supplying air and oxygen to the ice copper layer in the furnace through the oxygen lance, so that the total air quantity entering the furnace is kept to be 12000Nm/h, the oxygen entering the furnace is kept to be 500 plus-1200 Nm/h, and the oxygen-enriched oxygen concentration in the furnace is 21.3 percent, and then transferring the furnace body to a converting position for converting;
step S3: in the converting process, converting slag, matte and crude copper into a three-phase structure according to different specific gravities, wherein the temperature of a matte layer in a reaction zone is maintained at 1210 ℃; determining the liquid level in the furnace by measuring the thicknesses of the converting slag layer, the matte layer and the coarse copper layer, so that converting slag is discharged from a slag discharge port in time, and the liquid level of the coarse copper layer is discharged from a copper outlet when reaching an oxygen lance port;
step S4: when the converting furnace is used for slag and copper discharging, the temperature measuring gun is used for measuring the temperature of the converting furnace, the shaking frequency of the molten solution in the converting furnace is observed from the observation window, if the shaking frequency is high, the temperature is high, otherwise, the temperature is low, the temperature of the molten solution in the converting furnace is comprehensively judged through the shaking frequency and the measured temperature data of the temperature measuring gun, if the furnace temperature is high, the grade of matte is improved, the air inlet amount of the converting furnace is increased, the oxygen inlet amount is reduced, and the furnace temperature is adjusted by adding a residual electrode into the converting furnace, so that the furnace temperature is kept at 1200 +/-50 ℃.
In the blowing process, according to the temperature in the furnace and the blowing speed, the air inlet quantity and the oxygen quantity are adjusted by adopting two modes of large air quantity low oxygen concentration and small air quantity high oxygen concentration, so that the pressure in the furnace is kept stable.
Example 3
The continuous converting process for the high-grade matte in the embodiment comprises the following steps:
step S1: the smelting bottom blowing furnace quantitatively and periodically sends the thermal state copper matte into the blowing furnace according to 24 tons/hour through a connecting chute, wherein the grade of the thermal state copper matte is 76-78%;
step S2: opening a compressed air valve and an oxygen valve, setting the furnace entrance angle of an oxygen lance to be 60 degrees, setting the vertical height of the lower edge of an oxygen lance port to be 705mm from the bottom of the furnace, and enabling the oxygen lance to be positioned on an ice copper layer, directly supplying air and oxygen to the ice copper layer in the furnace through the oxygen lance, keeping the total air quantity entering the furnace to be 12000Nm/h, keeping the oxygen entering the furnace to be 500-1200Nm/h and the oxygen-enriched oxygen concentration in the furnace to be 21.3 percent, and then transferring the furnace body to a converting position for converting;
step S3: in the converting process, converting slag, matte and crude copper into a three-phase structure according to different specific gravities, wherein the temperature of a matte layer in a reaction zone is maintained at 1210 ℃; determining the liquid level in the furnace by measuring the thicknesses of the converting slag layer, the matte layer and the coarse copper layer, so that converting slag is discharged from a slag discharge port in time, and the liquid level of the coarse copper layer is discharged from a copper outlet when reaching an oxygen lance port;
step S4: when the converting furnace is used for slag and copper discharging, the temperature measuring gun is used for measuring the temperature of the converting furnace, the shaking frequency of the molten solution in the converting furnace is observed from the observation window, if the shaking frequency is high, the temperature is high, otherwise, the temperature is low, the temperature of the molten solution in the converting furnace is comprehensively judged through the shaking frequency and the measured temperature data of the temperature measuring gun, if the furnace temperature is high, the grade of matte is improved, the air inlet amount of the converting furnace is increased, the oxygen inlet amount is reduced, and the furnace temperature is adjusted by adding a residual electrode into the converting furnace, so that the furnace temperature is kept at 1200 +/-50 ℃.
In the blowing process, according to the temperature in the furnace and the blowing speed, the air inlet quantity and the oxygen quantity are adjusted by adopting two modes of large air quantity low oxygen concentration and small air quantity high oxygen concentration, so that the pressure in the furnace is kept stable.
In the above embodiment, as shown in fig. 1, the furnace entrance angle α of the oxygen lance is set to 30-60 °, and according to the production condition and the capacity, the oxygen lance can select different furnace entrance angle positions, and when the liquid level of the blister copper reaches the mouth of the oxygen lance, the copper is timely discharged through the copper outlet, so that the oxygen lance is always positioned at the junction of the matte layer or the matte layer and the blister copper layer, and the oxygen lance can be effectively protected.
In addition, the oxygen lance adopts double channels, the inner channel is filled with mixed gas of oxygen and compressed air, the outer channel is filled with compressed air, and the pressure of the outer channel is kept higher than that of the inner channel.
The above description is only for the preferred embodiment of the present invention, and is not intended to limit the present invention in any way. Any simple modifications, alterations and equivalent changes of the above embodiments according to the technical essence of the invention are still within the protection scope of the technical solution of the invention.

Claims (1)

1. A high-grade matte continuous converting process is characterized by comprising the following steps:
step S1: the smelting bottom blowing furnace is used for quantitatively and periodically feeding the thermal state matte into the blowing furnace according to the proportion of 24 tons/hour, wherein the thermal state matte grade is 76-78%;
step S2: opening a compressed air valve, setting the furnace inlet angle of an oxygen lance to be 49 degrees, setting the vertical height of the lower edge of an oxygen lance port to be 500mm from the furnace bottom, setting the injection point of the oxygen lance to be on an ice copper layer, supplying air into the furnace through the oxygen lance, keeping the total air quantity entering the furnace to be 12000Nm/h, keeping the oxygen entering amount to be 0Nm/h and the oxygen-enriched oxygen concentration in the furnace to be 21.3%, and then transferring the furnace body to a converting position for converting;
step S3: in the converting process, converting slag, matte and crude copper into a three-phase structure according to different specific gravities, wherein the temperature of a matte layer in a reaction zone is maintained at 1210 ℃; determining the liquid level in the furnace by measuring the thicknesses of the converting slag layer, the matte layer and the coarse copper layer, so that converting slag is discharged from a slag discharge port in time, and the liquid level of the coarse copper layer is discharged from a copper outlet when reaching an oxygen lance port;
step S4: when the converting furnace is used for slag and copper discharging, the temperature measuring gun is used for measuring the temperature of the converting furnace, the shaking frequency of a molten solution in the converting furnace is observed from an observation window, if the shaking frequency is high, the temperature is high, otherwise, the temperature is low, the temperature of the molten solution in the converting furnace is comprehensively judged through the shaking frequency and the measured temperature data of the temperature measuring gun, if the furnace temperature is high, the grade of matte is improved, the air inlet quantity of the converting furnace is improved, and the furnace temperature is adjusted by adding a residual electrode into the converting furnace, so that the furnace temperature is kept at 1200 +/-50 ℃;
under the condition of 12000Nm/h of blast volume in the furnace, the matte grade of the smelting furnace is 76-78%, pure air blowing is adopted, 24 tons of hot matte per hour, the full hot material blowing of the bottom blowing continuous converting furnace can be ensured, no intermediate cold material is added to control the melt in the furnace, and the required temperature of 1210 ℃ during normal production is reached.
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